Jack



1,583,416 N. W. LITTLEJOHNA4 JACK May 4 1926.

Filed Jan. 14. 1925 2 Smets-sheet' 1 Inman Mmm mgm/yb@ May 4 1926..

N. w. LITTLEJOHN JACK Filed Jan. 14`l 1935A 2 sneefs-sheeyz llmml mi.'/i 0 Ja Silicium! v new and useful Improveinents'iniJacks, of

Patented May y4, 1926.k g

NORMAN w. LITTLEJOHN, or Nnosno, MISSOURI, AssIGNotoNE-HAL To f: .l fSAMUEL A. KENQYER, or MIAMI, OKLAHOMA.. v

. JACK.

j `vimplicatin mea January V14, 1925.. serial nfaias;

To aZZQwLom) z'may concern.'

Be itknownthat 1,'NOR1IAN1W'. LITTLE- JOHN, a citizenfof 'the UnitedStates, residing at Neosho, in the county of Newton and State ofMissouri, have .invented certain whichthe following is a specification.

'Thisinvention relates to jacks, and morea Vp articul arlytofmeehanically op erated. jacks. v.An Aobject of the invention is the-provision of a jack that may be raisedor'lower'edwiththegsainefmotionfof the handle 4and which does not require thereversalothe pawls when' the lifting Ymen'iber' is to be Ymoved inareverse directionf: Y i l In the' present invention, I provide a pair ofpawls adapted to function 'as afholdin'g pawl anda lifting pawl whenthe.handle is movedthrough a predetermined arc, and I further provide a,latch cooperating with ithe two 'pawls which automatically unc tions torelease the pawls when'dthe handle mit the jack to be lowered.

Inthe accom anying drawings, I have shown one embo iment .of theinvention. In this showing: f F igurev 1 is a side elevation,

Figure 2 is a plan view, Y, i y .f

Figure 3 is a detail'sectional'view on line 3 8 of. Figure 1, j 1 'Y [j.Figure 4 is a vertical sectional view showis move'dthrough a second arcand thus per?v l fling vthe pawls and the latch, f

VFigure `5f is a .diagrammatic illustration of 'thepawllsand latch, I K''I'Figure e isfa horizontal sectional view on line' 6-`-6"of Figure 4, Ij

Figure `7 is la similar view' o-n line 7-7 of Figure ,4, and,

,iFigure4l` p .Y Y 0 .y A Referring to the drawings, the referencenumeralHl' designates .a "suitable base on Y 'which the jack ismounted.' An upright casing'2 isV arranged'on thefbase, A s shown, theVcasing is 4substantially U-shaped (seeFigures' 6 to 8) and isopen attherear.

The frontl-othecasing is provided with av slot4 'extending from a pointabove the base Vto the top. Adjacent the top of the casing,

l the sidewalls are providedtwith extensions 4 in vwhich the operatingmechanism is mounted. A plunger 5 is mounted'in the Zcasingfand`providedjwith 'rack' teethk 6 on Figure Sis ja slinilar vview oni-line8-#8 of .Y i I `l Alatch22 1s also pivotally mounted-on its rear face.'Thefupper end of thepluiigjer is provided with aseat or'rest 7f-for vthereception of aportionof the aXleor other V`member 8 is secured ltotheafront off'thc fplunger through theslot'l 3. 'As shown, the

auxiliary member V74im'ayybe `fastened yto the Vplunger by meansrofkscrews 9'or other sjuitableVK fastening velements vand' the adjacentso p vided withflugs or projections 10," adapted 'i tol be receivedinfcorresponding" openings or recesses in the face ofthe plunger. The"sidejwlallsuof the casing lare rproi'lidechwith inwardly extending 12',adaptedto formV guide'xfo'r.theplungein A gear or/:pinion 'isvmountedona pivot pin 14 arranged between the extensions 4 and is vprovided withteeth 15 Ameshing with the rack teeth G'of theplunger. *As shown (seeFigure 6), the ffgea'r is substantially lequal in widthy to the spaceV-between the ribs 12. .A handlev ,16`is also mounted on the i I pivotnin l'14. the handleheing1 bifurcated at its inner end. and.` being'provided with arms v17 extending on each side Otthegear' be- `tween thegear and the adjacent extension A 4A (see Figure 6). A mainfliftinggpawl17 f" his pivotally-mounted on pin 18"arran`ged 85 Y in thebifurcatedfportion ofl the'handle.

The lower end of the pawl is provided with va tooth 18 adapted to`engage beftween'the` teeth 155'0 the gear. vThe pawl-fisl provided;

with a curved face 19 and is provided with a pointed end v 20.arrang'gedr opposite the tooth 18. The upper end ofjfthe pawl iseX-tended, as at '21, forming a counter-balancing member.v

the handle, the latch vbeing vcarried by a vpivotpin 23 and the latch isprovided with a substantially straightfrontface 24, havon 'the rearendvof the main lifting pawl.

Ihe'jaclV is further lpro-vided with a holdvingpawl 27 which ispivotally mounted on a pin 28 arranged in theeXtensionsV-{lfbeneath 105the gear. The inner end ofthe pawl 'is proinga 'tootha2`5f at itsflowerend. -This tooth' .is adapted to engage fa1projection'26 formed 100yface of the auxiliary member ma'ybeprovided with a substantiallyarcuate extension 30 having a tooth 31 formed on its rear end.

A's'shown in Figures 1 to 3 of the drawingsthe handle 16 maybe hollowand suitable extensions 32 may be secured therein by 'means loffastening elements 33.

The upper ends ofthe extensions 4 are provided with rearwardly ertendingarmsV 34, adapted to receive a pin 35 whichV car.

ries a roller 36.

" In the lifting operation of the jack, the

is disengaged from the tooth on the holding pawl 27 and ,the holdingpawl swings by gravity to the dotted line position with the tooth l29 inengagement with the gear. This holds the plunger in a set position untilthe lifting pawl begins to` function. After the handle has reached thedotted line position,

it is moved downwardly. Due to the `counterbalance 21, thertooth 18 ofthe lifting pawl engages Vbetween two ofthe teeth of the gear and whenthe handle 'is moved downwardly, the gear is revolvedin a clockwisedirection, lifting Vthe plunger. This action is repeated'untiltheplunger has been raised the desired amount.

In lowering the plunger, the handle is swung from the position shown infull lines in Figure 4 of the drawingsto the position shown in dottedlines, VvVitli the Vparts in the full line position, 'the upper surfaceof the lifting pawl has engaged the roller 36 to swing the lift-ing'pawlon its pivot and cause the teeth v25 and 26 to engage each other. Thelifting tooth 18 is thus locked in an inoperative position and as thehandle is swung downwardly, no 'further lifting takes place. As thehandle approaches the dotted line position, the rear end of the holdingpawl forces the latch from engagement'with the liftiig pawl and onfurther Y downward movement, the latch engages the is to be taken as apreferred example' of the holding pawl. When the handle is then swungupwardly, the holding pawl is re-Y leased from vthe gear, which permitsthe plunger to lower under weight of the load.

Asr the -handleY approaches its upper limit,

same, and that various changes in the shape,

1.V In a lifting jack, a casing, plunger ,mounted in said casing,saidplunger being provided with rack teeth, a gear rotatably .mounted inVsaid. casing and meshing with said teeth, a handle pivotally mounted onsaid casing, a lifting pawl carried by said handle, a holding pawlpivotally mounted on said casing, means carried by .said'casing andadapted to 'engage said lifting pawl ywhen the handle is moved in agivenv direction to move said lifting pawl to an inoper ative position,and an automatically releasable latch adapted to engage saidVV liftingVpawl to retain it in inoperative. position Ywhen the handle is moved-inthe opposite direction. g, A

2. A device constructed Vin accordance with lclaim 1 wherein saidholdingpawl is adapted to vrelease said lifting pawl from said latchwhen the. handle is moved a predetermined distance in said last nameddirection. f

Vt. In a lifting jack, aV casing,a plunger mounted in said casing, saidplunger being Y provided with rack teeth, a gear rotatably mounted Ainsaid casing and meshing with said teeth, a handle kpivotallyA mounted onsaid casing, a lifting pawl Acarried by said handle, a holding'pawlpivotally mounted on said casing, means for yswinging said lifting pawlto an inoperative position when the handle -is moved inV one direction,and means for locking said lifting pawl inV inoperative positionwhensaid vhandle is moving in the opposite direction.

5.V In a liftingV jack, acasing, a plungermounted in said casing, saidplunger being provided with rack teeth, a gear rotatably mounted in saidcasing and meshing with said teeth, a handle pivotally mountedjon saidcasing, `a lifting pawl carried .by said handle, a holdingV pawlpivotally mounted on said casing, Va roller mounted on said casing andadapted to engage said lifting pawl when the handle is moved in a givendirection to move said lifting pawl to an inoperative position, and anautomatically releasable latch adapted to engage said lifting pawl.'

6. A device constructed in accordance with claim 5 wherein said holdingpawl is adapted to releasesaid lifting'ipawlfromY Y, said latch when thehandle is moved in the opposite direction.

7. A device constructed on said casing, a rearwardly extending mem berat the top of said casing adapted to contact with the upper end of saidlifting pawl in its full upward movement to release said lifting pawlfrom mesh with said gear, and an automatically releasable latch looselymounted on said handle and adapted to engage vsaid lifting pawl in itsinoperative position. l Y

9. In a lifting jack, a c-asing, a plunger mounted 'in said casing, saidplunger lbeing provided with rack teeth, a'gear rotatably ymounted insaid casing .and meshing with said teeth, a handle pivotally mounted onsaid casing, a lifting `pawl carried by said handle, a holding pawlpivotally mounted on said casing, a rearwardly extending member at thetop of said casing, a roller mounted aty the outer end of said memberand adapted to contact with said lifting pawl to move said lifting pawlto an inoperative position, and a latch loosely' mounted on said handleto hold said lifting pawl in inoperative position, said holding pawlbeing adapted to release .said lifting pawl from in accordanceL rwithclaim 5' wherein said holding pawl is said latch when :said handleismoved in .an

opposite direction.` y n,

j 10. In a lifting 'jaclna casing, a plunger mountedinsaid casing, said`plunger being vprovidedywith rackl teeth, a gear rotatabl mounted'insaid casing and meshing witi said teeth, a handle pivotally mounted onsaid casing, av lifting pawl carried by said handle, a holding pawlpivotally mounted 'on said casing, a rearwardly extending meinber at thetop of said casing, a roller mountedat the outer-,end of said member andadapted to contact with said lifting pawl fto move said lifting pawl toaninoperative v f position, and a latch loose-ly `mounted on l' saidhandle to hold said lifting pawl in inoperativeposition, said holdingpawl being adapted to release said lifting pawl from said latch whensaid handle is moved in an opposite direction,l and said latch beingthen adapted to engagesaid holding pawl VKwhereby said plunger will' belowered with a step by step movement. v Y

11. In a lifting jack, a support, a liftbar slidably connected to saidsupport,said lift bar being provided with rack teeth,a gear .meshingwith said teeth, a fixed pivot pin connected between said gear and saidsupport, a handle pivotally connected adjacent one endyof said pivotpin, aflifting pawl pivotally connected to said handle, a holdingpawlpivotally Amounted on said support, meanscarried by said supportadjacentthe top thereof for contacting with said lifting pawl to releaseit from engagement withY said gear, and a latch pivotally connected to4y said handle and adapted to engage said lift,-`

ing pawl to retain it in inoperative position when said handle is movinglin one direc-A tion. Y e

In testimony whereof, I aixmy signature.

NORMAN w- LITTLEJOHN

